That means consumers who rely on these products may be vulnerable to the effects of UV-A rays, including skin darkening, wrinkles, and skin cancer, in some cases.
The finding "is not surprising at all," Dr. Bruce Brod, a dermatologist at the University of Pennsylvania School of Medicine who was not involved in the study, told Reuters Health. "There's a lot of variability in these products."
Many companies sell facial creams claiming UV protection, including L'Oreal, Elizabeth Arden, and Mary Kay. But SPF levels on the bottle only reflect how much UV-B protection the product offers, and companies currently aren't required to back up UV-A claims on their labels, Dr. Steven Wang, the lead author on the study from Memorial Sloan-Kettering Cancer Center in New York City, told Reuters Health.
Even though UV-A and UV-B rays are about equally harmful, Wang said, "UV-A penetrates much deeper into the skin, which can also cause darkening of the skin as well as degrading and destroying the elastins and collagens," proteins in the skin that keep skin firm and protect against wrinkles.
The UV-A rays, Brod said, are "less involved with what we associate with a sunburn-type reaction." But, he said, "they do play a role in (skin) cancer - they damage the DNA of the cells over time."
And Wang pointed out that for many people, UV-A protection may be more important in a skin care product than UV-B protection. "In day-to-day living, most of the UV-B is completely blocked by windows, whereas the UV-A penetrates the windows," he said. "For most of us who work indoors, you really need more UV-A protection than UV-B protection."
Wang and his colleagues analyzed 29 daily facial creams that, according to their labels, protect against UV light. Some of the products claimed to protect against UV-A rays specifically, while others claimed general UV protection. The products had SPF labels from 15 to 50.
For more info- http://www.msnbc.msn.com/id/41142178/ns/health/
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